When our distant ancestors, whether homo erectus or homo habilis, came out of the trees and stood upright, some portions of descendant homo sapiens anatomy remained specifically vulnerable to insults associated with an erect posture and its necessary variations. A particular portion of anatomy vulnerable to the insults caused by stresses of physical exertion is the lumbar or lower back region. Leaning over from the erect position and lifting from the flexed position results in an unbalance in tone of the anterior and posterior muscle groups. The measured distance, between a point at the top of the shoulders and a point below the buttocks or gluteus, is three to ten inches longer in the bent over or hip-flexed position than when the person is standing erect, depending on the height, weight and muscular configuration of the particular individual.
The stress of this extension and the resulting strain on the muscles, ligaments and vertebrae of the spine is a cause of much pain and disability to many people in all segments of society, from farmers tilling the soil to secretaries filing documents, to athletes, librarians, and especially to manual laborers.
Prior efforts in this field include: U.S. Pat. No. 4,629,183, Perrine, disclosing an arm support device with a body member and pivotable arm supports; U.S. Pat. No. 4,802,667, Altner, a weight lifter's belt for the abdomen; U.S. Pat. No. 5,147,261, Smith et al, a lifting belt, comprising lumbar and abdominal belts; U.S. Pat. No. 5,158,520, Lemke et al., a training device comprising a belt on the subject attached to a weight lifting apparatus, U.S. Pat. No. 5,212,380, Steinbrueck, disclosing an orthopedic back harness suspended from an elevated support; U.S. Pat. No. 5,406,942, Loo, disclosing a harness with a belt, a suspender, a cross-support and an ischial pocket; and U.S. Pat. No. 5,472,398, Silverman, disclosing a harness for exercises having rigid shoulder yokes for holding weights during squat exercises.